Methods

The patients were divided into two groups (A and B) including 30 patients in each group.

Patients in these groups were matched according to their age, weight, height, gender, BMI and drug consumption.

In addition to standard asthma treatment (according to stepwise therapy in 4th step of bronchial asthma) in which the patients were controlled appropriately, group A received 1000 mg vitamin C daily and group B received placebo.

Results

At the baseline and after one month treatment, non–fasting blood samples were drawn for laboratory evaluations.

The mean (±SD) leukocyte vitamin C level in group A at the baseline and after one month treatment with 1000 mg/day vitamin C, were 0.0903 (±0.0787) µg/108 leukocytes and 0.1400 (±0.0953) µg/108 leukocytes respectively (P<0.05).

The mean (±SD) leukocyte vitamin C level in group B at the baseline and after one month administration of placebo, were 0.0867 (±0.0629) µg/108 leukocytes and 0.0805(±0.0736) µg/108 leukocytes respectively.

The leukocyte vitamin C level in group A was higher than those of group B after one month treatment with vitamin C and placebo and the difference was statistically significant (P<0.05).

Comparing PFT (FEV1, FVC and FEV1/FVC) in group B during the study period showed a significant increase in FEV1 (P<0.05), while the other two parameters remained unchanged.